Twin AQ130/ 250 trim fin settings

Hello, have a 1970's boat with twin AQ130 with Aquamatic 250 drives.The boat is quite in an original but very good shape - a bit of a wheeler dealers style - if you know the UK tv series.

But, does anyone know how to adjust the trim fins in a dual engine setting?

Service manual says nothing about twin engine setup in the 250 manual, but in Aquamatic 280 manual (page 140) there is quite much info - One should set the left fin 5 degrees and right 30 fin degrees to the port side.

In addition it says that in a twin installation one should have the toe-out angle set - 9/16" to 1" (15-25mm) so that the ends of the drive are that much closer.

Does all this apply to 250 or not - they are a bit different of course, or do you have any other comments?'

Jukka

The term "toe out" is used because the concerned lines are FWD of the stern drive pivoting points.
If we looked AFT only of the stern drives, it would appear to be "toed in".





The 250, 270 and 275 Trim Fin/Torque Tab is rather small and inefficient at correcting steer torque.
You can correct much of it, but do not expect to correct it all.